An electric vehicle drive-by-wire chassis power supply integrated management system

Abstract

The application relates to power management, in particular to a power supply comprehensive management system for an electric vehicle drive-by-wire chassis, which comprises a first power battery pack, a second power battery pack, a vehicle-mounted charging machine, a high-voltage distribution box and a power supply comprehensive controller; the high-voltage distribution box is used for charge-discharge switching of the first power battery pack and the second power battery pack and protection of a high-voltage circuit; the vehicle-mounted charging machine realizes electric energy supply in a charging mode and charges the first power battery pack and the second power battery pack through the high-voltage distribution box; the power supply comprehensive controller is responsible for processing information interaction in the system, realizes charge supply and discharge driving of the first power battery pack and the second power battery pack through the control logic of the charge and discharge and carries out fault alarm by controlling the high-voltage distribution box; the technical scheme provided by the application can effectively overcome the defects that the prior art cannot realize power energy redundancy design on the basis of balancing energy utilization and space utilization.

Description

Technical Field

[0001] This invention relates to power management, and more specifically to a comprehensive power management system for a drive-by-wire chassis of an electric vehicle. Background Technology

[0002] In recent years, as my country has continuously released positive signals encouraging the innovative development of new energy vehicles and intelligent connected vehicles, the corresponding R&D support from various provinces and cities has also increased. In addition, consumers' desire for the promotion and opening up of autonomous driving technology has become stronger, making the acceleration of the implementation and industrialization of related technologies a current trend.

[0003] For autonomous vehicles, the concept of redundant design in the control system renders traditional controllers unsuitable. A common approach is to use an onboard backup control board to activate the backup system in emergencies, ensuring the vehicle has at least the ability to provide early warning or short-term backup. However, for power batteries, maintaining the original design presents a significant challenge due to their large size and weight. Implementing a redundant design onboard system is extremely complex and difficult, yet it remains a crucial element for ensuring safe vehicle operation, making it a new area of ​​exploration.

[0004] In the pursuit of higher energy density, the design of power batteries for autonomous driving environments necessitates the use of technologies such as battery pack segmentation and primary / secondary separation to ensure vehicle mobility in emergency situations. The conventional design approach uses a large main power battery as the primary power source and a separate small battery pack as an auxiliary power source. While this achieves the desired result, it represents a compromise due to the low utilization rate of the auxiliary power source, its encroachment on space, and its inability to fully utilize the battery pack's inherent characteristics. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings of the existing technology, the present invention provides an electric vehicle drive-by-wire chassis power integrated management system, which can effectively overcome the defects of the existing technology that cannot achieve power energy redundancy design on the basis of balancing energy utilization and space utilization.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] An integrated power management system for a drive-by-wire chassis of an electric vehicle includes a first power battery pack, a second power battery pack, an on-board charger, a high-voltage distribution box, and a power integrated controller.

[0010] The high-voltage distribution box is used for switching between charging and discharging the first and second power battery packs, as well as for protecting the high-voltage circuit.

[0011] The on-board charger enables the supply of electrical energy in charging mode, and charges and replenishes the first power battery pack and the second power battery pack through the high-voltage power distribution box.

[0012] The power supply integrated controller is responsible for handling information interaction within the system. It uses the charging and discharging control logic to control the high-voltage power distribution box to realize the charging and discharging drive of the first and second power battery packs, and to provide fault alarms.

[0013] Preferably, the power supply integrated controller realizes the charging and discharging drive of the first power battery pack and the second power battery pack, and provides fault alarms through the following:

[0014] Vehicle power-on system self-test;

[0015] Autonomous identification of power battery packs;

[0016] Comprehensive discharge control of power battery packs;

[0017] Integrated charging control of the power battery pack.

[0018] Preferably, the autonomous identification of the power battery pack includes:

[0019] The power battery pack is identified by different arrangements of high and low voltage levels of the connector pins in the wiring harness assembly. The battery management system (BMS) of the power battery pack identifies the corresponding location attributes by comparing the voltage levels of the corresponding pins according to the pre-set arrangement configuration scheme, and then automatically pairs the communication ID of the power battery pack based on the location attributes.

[0020] Preferably, the comprehensive discharge control of the power battery pack includes:

[0021] A comprehensive evaluation of all power battery packs is conducted, and the comprehensive evaluation value of each power battery pack is calculated.

[0022] The calculated comprehensive evaluation values ​​are sorted in descending order to determine the priority of power battery pack discharge. The power integrated controller controls the comprehensive discharge of the power battery pack by controlling the high-voltage distribution box.

[0023] Preferably, the step of comprehensively evaluating all power battery packs and calculating the comprehensive evaluation value of each power battery pack includes:

[0024] By analyzing the messages sent by each node through the bus network, the battery state of charge (SOC), battery state of health (SOH), voltage (U), and fault code (Fault) of each power battery pack are read, and the comprehensive evaluation value T of each power battery pack is calculated using the following formula.n :

[0025] T n = (SOC n × a + SOH n × b + U × c) * (1 - Fault n )

[0026] Where, n is the label of the power battery pack, a is the weight corresponding to the state of charge SOC of the battery, b is the weight corresponding to the state of health SOH of the battery, and c is the weight corresponding to the voltage U.

[0027] Preferably, the calculated comprehensive evaluation values are sorted in descending order to determine the discharge priority arrangement of the power battery packs. The power supply comprehensive controller realizes the comprehensive discharge control of the power battery packs by controlling the high-voltage distribution box, including:

[0028] Taking the first power battery pack and the second power battery pack as examples, the process of comprehensive discharge control is as follows:

[0029] S1. Set the effective lower limit of the comprehensive evaluation value to 0.15, and judge the magnitude relationship between the comprehensive evaluation value T1 of the first power battery pack and the effective lower limit:

[0030] When T1 > 0.15, judge the magnitude relationship between the comprehensive evaluation value T2 of the second power battery pack and the effective lower limit. When T2 > 0.15, enter S2;

[0031] When T1 ≤ 0.15, judge the magnitude relationship between the comprehensive evaluation value T2 of the second power battery pack and the effective lower limit. When T2 ≤ 0.15, enter S3; when T2 > 0.15, enter S5;

[0032] S2. Judge the magnitude relationship between T1 and T2:

[0033] When T1 > T2, enter S4; when T1 < T2, enter S5;

[0034] S3. The power supply comprehensive management system implements driving mode switching intervention;

[0035] S4. The first power battery pack is selected as the discharge object. At this time, the power supply comprehensive management system sends an instruction to close the internal main relay KM1 to the battery management system BMS of the first power battery pack through the CAN bus, correspondingly controls the internal relay KM3 of the high-voltage distribution box to close, then closes the pre-charge relay KM5. After pre-charging for 1 s, then closes the discharge main relay KM6 and disconnects the pre-charge relay KM5. The high-voltage power-on is completed, and enter S6;

[0036] S5. The second power battery pack is selected as the discharge target. At this time, the power integrated management system sends the internal main relay KM2 closing command to the battery management system BMS of the second power battery pack through the CAN bus. Correspondingly, it controls the internal relay KM4 of the high voltage distribution box to close, and then closes the pre-charge relay KM5. After pre-charging for 1 second, the discharge main relay KM6 is closed and the pre-charge relay KM5 is opened. The high voltage power-on is completed and enters S6.

[0037] S6. During normal vehicle operation, the comprehensive evaluation values ​​of each power battery pack are continuously detected, compared, and analyzed to achieve real-time monitoring of battery swapping needs. When the comprehensive evaluation value T of the discharge target is detected... n When the value is ≤0.15, battery swapping will be implemented.

[0038] When the current discharge target is the first power battery pack, proceed to S7; when the current discharge target is the second power battery pack, proceed to S8.

[0039] S7. The power integrated management system sends a closing command for the internal main relay KM2 to the battery management system BMS of the undischarged second power battery pack via the CAN bus, which in turn controls the internal relay KM4 of the high-voltage distribution box to close, and then disconnects the relay KM3. The system then sends a disconnect command for the internal main relay KM1 to the battery management system BMS of the discharged first power battery pack via the CAN bus, thus completing the high-voltage battery swap.

[0040] When the comprehensive evaluation value T2 of the second power battery pack is ≤ 0.15, proceed to S3;

[0041] S8. The power integrated management system sends a closing command for the internal main relay KM1 to the battery management system BMS of the undischarged first power battery pack via the CAN bus, which in turn controls the internal relay KM3 of the high-voltage distribution box to close and then disconnects relay KM4. The system then sends a disconnect command for the internal main relay KM2 to the battery management system BMS of the discharged second power battery pack via the CAN bus, thus completing the high-voltage battery swap.

[0042] When the comprehensive evaluation value T1 of the first power battery pack is less than or equal to 0.15, proceed to step S3.

[0043] Preferably, the power supply integrated management system implements driving mode switching intervention, including:

[0044] When the comprehensive evaluation value T of all power battery packs n When the current is less than or equal to 0.15, the power management system sends a driving mode switching request to the motor controller, requesting to enter limp mode to forcibly limit the demand current, ensuring the vehicle's continued driving capability, and at the same time outputs an alarm indicating the need to replace the power battery pack.

[0045] When a new power battery pack is detected and the comprehensive evaluation value Tn When it is greater than 0.15, immediately switch the power supply battery pack and send a driving mode switching request to the motor controller, requesting to re-enter the normal driving mode.

[0046] Preferably, the comprehensive charging control of the battery pack includes:

[0047] When the vehicle needs to be charged, the on-board charger outputs a charging wake-up signal to the online battery pack to activate the battery management system BMS of all battery packs;

[0048] The power comprehensive controller preferentially charges the battery pack with a lower state of charge according to the state of charge of each battery pack. When the state of charge of the charging object reaches 85%, replace the charging control; when the state of charge of all battery packs reaches 85%, perform simultaneous charging control.

[0049] Preferably, taking the first battery pack and the second battery pack as an example, where SOC2 < SOC1 < 85%, the process of comprehensive charging control is as follows:

[0050] S1. The power comprehensive management system sends an instruction to close the internal main relay KM2 to the battery management system BMS of the second battery pack through the CAN bus. The second battery pack performs self-check. When there is no fault, it enters S2; when there is a fault, it enters S7;

[0051] S2. The battery management system BMS of the second battery pack controls the internal main relay KM2 to close. The power comprehensive management system controls the internal relay KM4 and the charging relay KM7 in the high-voltage distribution box to close, and starts to charge the second battery pack;

[0052] When it is detected that the state of charge SOC2 of the second battery pack reaches 85%, it enters S3;

[0053] S3. The power comprehensive management system sends an instruction to close the internal main relay KM1 to the battery management system BMS of the first battery pack through the CAN bus. The first battery pack performs self-check. When there is no fault, it enters S4; when there is a fault, it enters S8;

[0054] S4. The battery management system BMS of the first battery pack controls the internal main relay KM1 to close. The power comprehensive management system sends an instruction to open the internal main relay KM2 to the battery management system BMS of the second battery pack through the CAN bus. The battery management system BMS of the second battery pack controls the internal main relay KM2 to open. The power comprehensive management system controls the internal relay KM3 in the high-voltage distribution box to close, and then disconnects the relay KM4, and starts to charge the first battery pack;

[0055] When the state of charge (SOC1) of the first power battery pack is detected to reach 85%, proceed to step S5.

[0056] S5. The power management system sends a closing command for the internal main relay KM2 to the battery management system (BMS) of the second power battery pack via the CAN bus. The BMS of the second power battery pack controls the closing of the internal main relay KM2, and the power management system controls the closing of the internal relay KM4 of the high-voltage distribution box to start charging the two power battery packs together.

[0057] When it is detected that the state of charge of both power battery packs has reached 100%, proceed to S6;

[0058] S6. The power management system sends the disconnect command of the main relays KM1 and KM2 inside the battery pack through the CAN bus. The battery management system (BMS) of the first power battery pack and the second power battery pack respectively controls the internal main relays KM1 and KM2 to disconnect. The power management system controls the internal relays KM3, KM4 and charging relay KM7 of the high voltage distribution box to disconnect, and the charging is completed.

[0059] S7, Power Management System outputs an alarm, enters S3;

[0060] S8, the power management system outputs an alarm and terminates charging.

[0061] Preferably, it also includes a portable charger, the input and output interfaces of which are customized, adopt a high-low voltage hybrid interface, and are the same as the plug-in connector of the power battery pack, and have an internal external high-level power supply.

[0062] When the portable charger is plugged into the power battery pack, the battery management system (BMS) of the power battery pack will be activated, enabling offline charging of the power battery pack, which is suitable for use in temporary charging stations.

[0063] (III) Beneficial Effects

[0064] Compared with existing technologies, the electric vehicle drive-by-wire chassis power integrated management system provided by this invention, within a certain chassis layout space, utilizes a dual-mode charging and swapping arrangement and incorporates a power integrated management solution based on an unfair scheduling mechanism. This not only optimizes the energy flow of the entire vehicle but also improves the utilization rate of the layout space. It effectively achieves redundant design of power energy while coordinating energy utilization and space utilization, thereby improving the safe driving of autonomous vehicles. At the same time, it can also optimize the use of existing resources and achieve optimal energy use. Attached Figure Description

[0065] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0066] Figure 1 This is a schematic diagram of the system of the present invention;

[0067] Figure 2 This is a schematic diagram illustrating the autonomous identification of the power battery pack using connectors in this invention.

[0068] Figure 3 This is the electrical schematic diagram of the high-voltage distribution box in this invention;

[0069] Figure 4 This is a schematic diagram of the process for comprehensive discharge control of the power battery pack in this invention;

[0070] Figure 5 This is a schematic diagram of the process for integrated charging control of the power battery pack in this invention. Detailed Implementation

[0071] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0072] An integrated power management system for electric vehicle drive-by-wire chassis, such as Figure 1 As shown, it includes a first power battery pack, a second power battery pack, an on-board charger, a high-voltage distribution box, and a power integrated controller;

[0073] The high-voltage distribution box is used for switching between charging and discharging the first and second power battery packs, as well as for protecting the high-voltage circuit.

[0074] The on-board charger enables the supply of electrical energy in charging mode, and charges and replenishes the first power battery pack and the second power battery pack through the high-voltage power distribution box.

[0075] The power supply integrated controller is responsible for handling information interaction within the system. It uses the charging and discharging control logic to control the high-voltage power distribution box to realize the charging and discharging drive of the first and second power battery packs, and to provide fault alarms.

[0076] The technical solution of this application also includes a portable charger. The input and output interfaces of the portable charger are customized, and a high-low voltage hybrid interface is adopted. It is the same as the plug-in of the power battery pack and has an internal external high-level power supply.

[0077] When the portable charger is plugged into the power battery pack, the battery management system (BMS) of the power battery pack will be activated, enabling offline charging of the power battery pack, which is suitable for use in temporary charging stations.

[0078] The power supply integrated controller achieves charging and discharging of the first and second power battery packs and provides fault alarms through the following methods:

[0079] Vehicle power-on system self-test;

[0080] Autonomous identification of power battery packs;

[0081] Comprehensive discharge control of power battery packs;

[0082] Integrated charging control of the power battery pack.

[0083] ① The vehicle's power-on system self-test includes:

[0084] When the vehicle is powered on, the ON wake-up signal activates the battery management system (BMS) of all parallel-connected power battery packs on the vehicle, and each BMS performs a self-test.

[0085] ② Autonomous identification of power battery packs, including:

[0086] The power battery pack is identified by different arrangements of high and low voltage levels of the connector pins in the wiring harness assembly. The battery management system (BMS) of the power battery pack identifies the corresponding location attributes by comparing the voltage levels of the corresponding pins according to the pre-set arrangement configuration scheme, and then automatically pairs the communication ID of the power battery pack based on the location attributes.

[0087] like Figure 2 As shown, the connector has three pins (pins 13, 14, and 15) designated as dedicated pins for identifying the power battery pack. By inputting high and low levels to the corresponding pins on the wiring harness, the automatic identification of the power battery pack's location is achieved.

[0088] Based on the fundamental understanding of permutations and combinations, the high and low levels of three pins can identify eight power battery packs, which can basically meet the power battery pack quantity requirements of most single vehicles. Specifically, the communication ID of all power battery packs is initialized to 0x200 at the factory. When the level of pins 13-14-15 is high-low-low, the corresponding power battery pack's Battery Management System (BMS) assigns a communication ID of 0x200 + Node ID. At this time, Node ID = 1, so it is identified as power battery pack No. 1, and the communication ID is 0x201; when the level of pins 13-14-15 is low-high-low, Node ID = 2, so it is identified as power battery pack No. 2, and the communication ID is 0x202; when the level of pins 13-14-15 is low-low-high, Node ID = 3, so it is identified as power battery pack No. 3, and the communication ID is 0x203; and so on, completing the autonomous identification and communication ID assignment of each power battery pack.

[0089] ③Comprehensive discharge control of the power battery pack, including:

[0090] A comprehensive evaluation of all power battery packs is conducted, and the comprehensive evaluation value of each power battery pack is calculated.

[0091] The calculated comprehensive evaluation values ​​are sorted in descending order to determine the priority of power battery pack discharge. The power integrated controller controls the comprehensive discharge of the power battery pack by controlling the high-voltage distribution box.

[0092] 1) Conduct a comprehensive evaluation of all power battery packs and calculate the comprehensive evaluation value of each power battery pack, including:

[0093] By analyzing the messages sent by each node through the bus network, the battery state of charge (SOC), battery state of health (SOH), voltage (U), and fault code (Fault) of each power battery pack are read, and the comprehensive evaluation value T of each power battery pack is calculated using the following formula. n :

[0094] T n =(SOC) n ×a+SOH n ×b+U×c)*(1-Fault n )

[0095] Where n is the label of the power battery pack, a is the weight corresponding to the battery state of charge (SOC), a = 0.3, b is the weight corresponding to the battery state of health (SOH), b = 0.4, and c is the weight corresponding to the voltage U, c = 0.3.

[0096] 2) such as Figure 3 and Figure 4As shown, the calculated comprehensive evaluation values are sorted in descending order to determine the discharge priority arrangement of the power battery pack. The power supply comprehensive controller realizes the comprehensive discharge control of the power battery pack by controlling the high-voltage distribution box, including:

[0097] Taking the first power battery pack and the second power battery pack as examples, the process of comprehensive discharge control is as follows:

[0098] S1. Set the effective lower limit of the comprehensive evaluation value to 0.15, and judge the magnitude relationship between the comprehensive evaluation value T1 of the first power battery pack and the effective lower limit:

[0099] When T1 > 0.15, judge the magnitude relationship between the comprehensive evaluation value T2 of the second power battery pack and the effective lower limit. When T2 > 0.15, enter S2;

[0100] When T1 ≤ 0.15, judge the magnitude relationship between the comprehensive evaluation value T2 of the second power battery pack and the effective lower limit. When T2 ≤ 0.15, enter S3; when T2 > 0.15, enter S5;

[0101] S2. Judge the magnitude relationship between T1 and T2:

[0102] When T1 > T2, enter S4; when T1 < T2, enter S5;

[0103] S3. The power supply comprehensive management system implements driving mode switching intervention;

[0104] S4. The first power battery pack is selected as the discharge object. At this time, the power supply comprehensive management system sends an internal main relay KM1 closing instruction to the battery management system BMS of the first power battery pack through the CAN bus, correspondingly controls the internal relay KM3 of the high-voltage distribution box to close, then closes the pre-charge relay KM5. After pre-charging for 1 s, then closes the discharge main relay KM6 and disconnects the pre-charge relay KM5. After the high-voltage power-on is completed, enter S6;

[0105] S5. The second power battery pack is selected as the discharge object. At this time, the power supply comprehensive management system sends an internal main relay KM2 closing instruction to the battery management system BMS of the second power battery pack through the CAN bus, correspondingly controls the internal relay KM4 of the high-voltage distribution box to close, then closes the pre-charge relay KM5. After pre-charging for 1 s, then closes the discharge main relay KM6 and disconnects the pre-charge relay KM5. After the high-voltage power-on is completed, enter S6;

[0106] S6. During the normal driving process of the vehicle, continuously detect, compare and analyze the comprehensive evaluation values of each power battery pack to realize real-time monitoring of the battery replacement demand. When the comprehensive evaluation value T of the discharge object n ≤ 0.15, implement battery replacement:

[0107] When the current discharge target is the first power battery pack, proceed to S7; when the current discharge target is the second power battery pack, proceed to S8.

[0108] S7. The power integrated management system sends a closing command for the internal main relay KM2 to the battery management system BMS of the undischarged second power battery pack via the CAN bus, which in turn controls the internal relay KM4 of the high-voltage distribution box to close, and then disconnects the relay KM3. The system then sends a disconnect command for the internal main relay KM1 to the battery management system BMS of the discharged first power battery pack via the CAN bus, thus completing the high-voltage battery swap.

[0109] When the comprehensive evaluation value T2 of the second power battery pack is ≤ 0.15, proceed to S3;

[0110] S8. The power integrated management system sends a closing command for the internal main relay KM1 to the battery management system BMS of the undischarged first power battery pack via the CAN bus, which in turn controls the internal relay KM3 of the high-voltage distribution box to close and then disconnects relay KM4. The system then sends a disconnect command for the internal main relay KM2 to the battery management system BMS of the discharged second power battery pack via the CAN bus, thus completing the high-voltage battery swap.

[0111] When the comprehensive evaluation value T1 of the first power battery pack is less than or equal to 0.15, proceed to step S3.

[0112] 3) The power supply integrated management system implements driving mode switching intervention, including:

[0113] When the comprehensive evaluation value T of all power battery packs n When the current is less than or equal to 0.15, the power management system sends a driving mode switching request to the motor controller, requesting to enter limp mode to forcibly limit the demand current, ensuring the vehicle's continued driving capability, and at the same time outputs an alarm indicating the need to replace the power battery pack.

[0114] When a new power battery pack is detected and the comprehensive evaluation value T n When the value is greater than 0.15, the power supply battery pack is immediately switched to the power supply, and a driving mode switching request is sent to the motor controller to request to re-enter the normal driving mode.

[0115] ④ Integrated charging control of the power battery pack, including:

[0116] When the vehicle needs to be charged, the on-board charger outputs a charging wake-up signal to the online power battery pack, activating the battery management system (BMS) of all power battery packs.

[0117] The power supply integrated controller preferentially charges the power battery pack with a lower state of charge according to the state of charge of each power battery pack. When the state of charge of the charging object reaches 85%, charging control is switched; when the state of charge of all power battery packs reaches 85%, simultaneous charging control is carried out.

[0118] As Figure 3 and Figure 5 shown, taking the first power battery pack and the second power battery pack as an example, where SOC2 < SOC1 < 85%, the process of comprehensive charging control is as follows:

[0119] S1. The power supply integrated management system sends an instruction to close the internal main relay KM2 to the battery management system BMS of the second power battery pack through the CAN bus. The second power battery pack performs self-check. When there is no fault, it enters S2; when there is a fault, it enters S7;

[0120] S2. The battery management system BMS of the second power battery pack controls the internal main relay KM2 to close. The power supply integrated management system controls the internal relay KM4 and the charging relay KM7 in the high-voltage distribution box to close, and starts to charge the second power battery pack;

[0121] When it is detected that the state of charge SOC2 of the second power battery pack reaches 85%, it enters S3;

[0122] S3. The power supply integrated management system sends an instruction to close the internal main relay KM1 to the battery management system BMS of the first power battery pack through the CAN bus. The first power battery pack performs self-check. When there is no fault, it enters S4; when there is a fault, it enters S8;

[0123] S4. The battery management system BMS of the first power battery pack controls the internal main relay KM1 to close. The power supply integrated management system sends an instruction to open the internal main relay KM2 to the battery management system BMS of the second power battery pack through the CAN bus. The battery management system BMS of the second power battery pack controls the internal main relay KM2 to open. The power supply integrated management system controls the internal relay KM3 in the high-voltage distribution box to close, and then disconnects the relay KM4, and starts to charge the first power battery pack;

[0124] When it is detected that the state of charge SOC1 of the first power battery pack reaches 85%, it enters S5;

[0125] S5. The power supply integrated management system sends an instruction to close the internal main relay KM2 to the battery management system BMS of the second power battery pack through the CAN bus. The battery management system BMS of the second power battery pack controls the internal main relay KM2 to close. The power supply integrated management system controls the internal relay KM4 in the high-voltage distribution box to close, and starts to charge the two power battery packs together;

[0126] When it is detected that the state of charge of both power battery packs has reached 100%, proceed to S6;

[0127] S6. The power management system sends the disconnect command of the main relays KM1 and KM2 inside the battery pack through the CAN bus. The battery management system (BMS) of the first power battery pack and the second power battery pack respectively controls the internal main relays KM1 and KM2 to disconnect. The power management system controls the internal relays KM3, KM4 and charging relay KM7 of the high voltage distribution box to disconnect, and the charging is completed.

[0128] S7, Power Management System outputs an alarm, enters S3;

[0129] S8, the power management system outputs an alarm and terminates charging.

[0130] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A comprehensive power management system for a drive-by-wire chassis of an electric vehicle, characterized in that: It includes a first power battery pack, a second power battery pack, an on-vehicle charger, a high-voltage distribution box, and a power supply integrated controller; The high-voltage distribution box is used for the charge and discharge switching of the first power battery pack and the second power battery pack, and for protecting the high-voltage circuit; The on-vehicle charger realizes the power supply in the charging mode and charges the first power battery pack and the second power battery pack through the high-voltage distribution box; The power supply integrated controller is responsible for processing the information interaction within the system, and realizes the charging replenishment and discharge drive of the first power battery pack and the second power battery pack by controlling the high-voltage distribution box using the charge and discharge control logic, and conducts fault alarm; The power supply integrated controller realizes the charging replenishment and discharge drive of the first power battery pack and the second power battery pack, and conducts fault alarm through the following: The vehicle power-on system conducts self-check; The power battery pack conducts autonomous identification; The comprehensive discharge control of the power battery pack; The comprehensive charging control of the power battery pack; The comprehensive discharge control of the power battery pack includes: Comprehensively evaluate all power battery packs, calculate the comprehensive evaluation value of each power battery pack, specifically including: By analyzing the messages sent by each node through the bus network, the battery state of charge (SOC), battery state of health (SOH), voltage (U), and fault code (Fault) of each power battery pack are read, and the comprehensive evaluation value T of each power battery pack is calculated using the following formula. n : Where n is the label of the power battery pack, a is the weight corresponding to the battery state of charge (SOC), b is the weight corresponding to the battery state of health (SOH), and c is the weight corresponding to the voltage U. Sort the calculated comprehensive evaluation values in descending order to determine the discharge priority arrangement of the power battery packs. The power supply integrated controller realizes the comprehensive discharge control of the power battery packs by controlling the high-voltage distribution box.

2. The electric vehicle drive-by-wire chassis power integrated management system according to claim 1, characterized in that: The autonomous identification of the power battery pack includes: Realize the identification of the power battery pack through different permutations and combinations of the high and low levels of the pins of the connectors in the harness assembly. The battery management system BMS of the power battery pack compares and identifies the corresponding position attributes according to the level states of the corresponding pins according to the pre-set permutation and combination configuration scheme, and then realizes the automatic pairing of the communication ID of the power battery pack according to the position attributes.

3. The electric vehicle drive-by-wire chassis power integrated management system according to claim 1, characterized in that: The sorting of the calculated comprehensive evaluation values in descending order to determine the discharge priority arrangement of the power battery packs, and the power supply integrated controller realizes the comprehensive discharge control of the power battery packs by controlling the high-voltage distribution box, includes: Taking the first power battery pack and the second power battery pack as examples, the process of comprehensive discharge control is as follows: S1. Set the effective lower limit of the comprehensive evaluation value to 0.15, and judge the size of the comprehensive evaluation value T1 of the first power battery pack and the effective lower limit: When T1 > 0.15, judge the size of the comprehensive evaluation value T2 of the second power battery pack and the effective lower limit. When T2 > 0.15, enter S2; When T1 ≤ 0.15, judge the size of the comprehensive evaluation value T2 of the second power battery pack and the effective lower limit. When T2 ≤ 0.15, enter S3; when T2 > 0.15, enter S5; S2. Judge the size of T1 and T2: When T1 > T2, enter S4; when T1 < T2, enter S5; S3. The power supply comprehensive management system implements driving mode switching intervention; S4. The first power battery pack is selected as the discharging object. At this time, the power supply integrated management system sends an instruction to close the internal main relay KM1 to the battery management system BMS of the first power battery pack through the CAN bus, correspondingly controls the internal relay KM3 in the high-voltage distribution box to close, then closes the pre-charge relay KM5. After pre-charging for 1 s, closes the discharging main relay KM6, and disconnects the pre-charge relay KM5. The high-voltage power-on is completed and enters S6; S5. The second power battery pack is selected as the discharging object. At this time, the power supply integrated management system sends an instruction to close the internal main relay KM2 to the battery management system BMS of the second power battery pack through the CAN bus, correspondingly controls the internal relay KM4 in the high-voltage distribution box to close, then closes the pre-charge relay KM5. After pre-charging for 1 s, closes the discharging main relay KM6, and disconnects the pre-charge relay KM5. The high-voltage power-on is completed and enters S6; S6. During normal vehicle operation, the comprehensive evaluation values ​​of each power battery pack are continuously detected, compared, and analyzed to achieve real-time monitoring of battery swapping needs. When the comprehensive evaluation value T of the discharge target is detected... n When the value is ≤0.15, battery swapping will be implemented. When the current discharging object is the first power battery pack, it enters S7; when the current discharging object is the second power battery pack, it enters S8; S7. The power supply integrated management system sends an instruction to close the internal main relay KM2 to the battery management system BMS of the second power battery pack that has not been discharged through the CAN bus, correspondingly controls the internal relay KM4 in the high-voltage distribution box to close, then disconnects the relay KM3, and sends an instruction to disconnect the internal main relay KM1 to the battery management system BMS of the discharging first power battery pack through the CAN bus. The high-voltage battery swapping is completed; When the comprehensive evaluation value T2 of the second power battery pack ≤ 0.15, it enters S3; S8. The power supply integrated management system sends an instruction to close the internal main relay KM1 to the battery management system BMS of the first power battery pack that has not been discharged through the CAN bus, correspondingly controls the internal relay KM3 in the high-voltage distribution box to close, then disconnects the relay KM4, and sends an instruction to disconnect the internal main relay KM2 to the battery management system BMS of the discharging second power battery pack through the CAN bus. The high-voltage battery swapping is completed; When the comprehensive evaluation value T1 of the first power battery pack ≤ 0.15, it enters S3.

4. The electric vehicle drive-by-wire chassis power integrated management system according to claim 3, characterized in that: The power supply integrated management system implements driving mode switching intervention, including: When the comprehensive evaluation value T of all power battery packs n When the current is less than or equal to 0.15, the power management system sends a driving mode switching request to the motor controller, requesting to enter limp mode to forcibly limit the demand current, ensuring the vehicle's continued driving capability, and at the same time outputs an alarm indicating the need to replace the power battery pack. When a new power battery pack is detected and the comprehensive evaluation value T n When the value is greater than 0.15, the power supply battery pack is immediately switched to the power supply, and a driving mode switching request is sent to the motor controller to request to re-enter the normal driving mode.

5. The electric vehicle drive-by-wire chassis power integrated management system according to claim 1, characterized in that: The comprehensive charging control of the power battery pack includes: When the vehicle needs to be charged, the on-vehicle charger outputs a charging wake-up signal to the online power battery pack to activate the battery management systems BMS of all power battery packs; The power supply integrated controller preferentially charges the power battery pack with a smaller state of charge according to the state of charge of each power battery pack. When the state of charge of the charging object reaches 85%, it performs replacement charging control; when the state of charge of all power battery packs reaches 85%, it performs simultaneous charging control.

6. The electric vehicle drive-by-wire chassis power integrated management system according to claim 5, characterized in that: Taking the first power battery pack and the second power battery pack, and SOC2 < SOC1 < 85% as an example, the process of comprehensive charging control is as follows: S1. The power supply integrated management system sends an instruction to close the internal main relay KM2 to the battery management system BMS of the second power battery pack through the CAN bus. The second power battery pack performs self-check. When there is no fault, it enters S2; when there is a fault, it enters S7; S2. The battery management system (BMS) of the second power battery pack controls the internal main relay KM2 to close, and the power integrated management system controls the internal relays KM4 and KM7 of the high-voltage distribution box to close, so as to start charging the second power battery pack. When the state of charge (SOC2) of the second power battery pack is detected to reach 85%, proceed to S3. S3. The power integrated management system sends the internal main relay KM1 closing command to the battery management system (BMS) of the first power battery pack via the CAN bus. The first power battery pack performs a self-test. If there is no fault, it enters S4; if there is a fault, it enters S8. S4. The battery management system (BMS) of the first power battery pack controls the internal main relay KM1 to close. The power integrated management system sends a command to the battery management system (BMS) of the second power battery pack to open the internal main relay KM2 via the CAN bus. The battery management system (BMS) of the second power battery pack controls the internal main relay KM2 to open. The power integrated management system controls the internal relay KM3 of the high-voltage distribution box to close, and then opens the relay KM4 to start charging the first power battery pack. When the state of charge (SOC1) of the first power battery pack is detected to reach 85%, proceed to step S5. S5. The power management system sends a closing command for the internal main relay KM2 to the battery management system (BMS) of the second power battery pack via the CAN bus. The BMS of the second power battery pack controls the closing of the internal main relay KM2, and the power management system controls the closing of the internal relay KM4 of the high-voltage distribution box to start charging the two power battery packs together. When it is detected that the state of charge of both power battery packs has reached 100%, proceed to S6. S6. The power management system sends the disconnect command of the main relays KM1 and KM2 inside the battery pack through the CAN bus. The battery management system (BMS) of the first power battery pack and the second power battery pack respectively controls the internal main relays KM1 and KM2 to disconnect. The power management system controls the internal relays KM3, KM4 and charging relay KM7 of the high voltage distribution box to disconnect, and the charging is completed. S7, Power Management System outputs an alarm, enters S3; S8, the power management system outputs an alarm and terminates charging.

7. The electric vehicle drive-by-wire chassis power integrated management system according to any one of claims 1-6, characterized in that: It also includes a portable charger, whose input and output interfaces are customized, adopting a high-low voltage hybrid interface, the same as the power battery pack's connector, and has an internal external high-level power supply. When the portable charger is plugged into the power battery pack, the battery management system (BMS) of the power battery pack will be activated, enabling offline charging of the power battery pack, which is suitable for use in temporary charging stations.

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